000 AXNT20 KNHC 292346 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED OCT 29 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ADDED TO THE 1800 UTC SURFACE ANALYSIS ALONG 22W/23W SOUTH OF 16N BASED SATELLITE PICTURES...SURFACE DATA AND ASCAT PAST FROM AROUND 1134 UTC THAT SHOWED THE WIND SHIFT ASSOCIATED WITH THE WAVE AND SOME CYCLONIC CIRCULATION NEAR 11N. IN ADDITION...THE HOVMOLLER DIAGRAM INDICATES THE WWD PROPAGATION OF THIS SYSTEM AND THE WAVE SHOWS UP VERY WELL IN THE TPW PRODUCT FROM CIMSS WHERE A BULGE OF MOISTURE IS SEEN. THIS IS THE 60TH TROPICAL WAVE TPC/NHC HAS TRACKED THIS SEASON. SCATTERED MODERATE CONVECTION IS WITHIN 80-100 NM EITHER SIDE OF THE WAVE AXIS FROM 11N-13N. THE WAVE IS CURRENTLY APPROACHING THE CAPE VERDE ISLANDS. A TROPICAL WAVE IS ALONG 52W/53W S OF 16N MOVING W 10-15 KT. THE WAVE IS BENEATH STRONG UPPER SLY FLOW AHEAD OF AN UPPER-LEVEL TROUGH WITH AXIS ACROSS THE TROPICAL NORTH ATLC. MAINLY HIGH CLOUDS ARE NOTED BEHIND THE WAVE AXIS WITH SOME SHOWER ACTIVITY NEAR THE INTERSECTION OF THE WAVE LINE AND THE ITCZ. A TROPICAL WAVE IS OVER THE EASTERN CARIBBEAN ALONG 65W SOUTH OF 19N MOVING W 10-15 KT. AN INVERTED-V SIGNATURE IS SEEN ON LATEST VIS SATELLITE IMAGERY FOR THE DAY. THIS SYSTEM IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE VIRGIN ISLANDS AND PARTS OF PUERTO RICO EARLY THIS EVENING. SOME SHOWER ACTIVITY IS ALSO APPROACHING THE ABC ISLANDS. ...THE ITCZ... ITCZ AXIS IS ANALYZED ALONG 11N15W 10N30W 11N39W 8N50W 8N60W. A SURFACE TROUGH REMAINS EMBEDDED WITHIN THE ITCZ ALONG 41W FROM 8N-15N WITH A 1012 MB LOW ALONG THE TROUGH NEAR 11N. THIS FEATURE IS DRIFTING WEST-NORTHWESTWARD. THE ASSOCIATED SHOWER ACTIVITY REMAINS DISORGANIZED WITH A COUPLE OF CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION NEAR 18N38W...AND JUST NE OF THE LOW CENTER NEAR 12N41W. UPPER-LEVEL WINDS ARE FORECAST TO REMAIN UNFAVORABLE FOR SIGNIFICANT DEVELOPMENT DURING THE NEXT COUPLE OF DAYS. ELSEWHERE...SCATTERED MODERATE CONVECTION IS FROM 6N-8N BETWEEN 24W-27W AND FROM 9N-11N BETWEEN 43W-49W. ...DISCUSSION... GULF OF MEXICO... HIGH PRES CENTERED OVER THE SE CONUS EXTENDS A RIDGE OVER THE ENTIRE GULF REGION. THE RIDGE ALSO ENVELOPS THE FLORIDA PENINSULA...MUCH OF CUBA...THE YUCATAN PENINSULA AND EASTERN MEXICO GIVING THE AREA A MOSTLY DRY AND STABLE ATMOSPHERE. WINDS ARE BEGINNING TO VEER TO THE NE GRADUALLY MODIFYING THE AIR MASS. THIS TREND WILL CONTINUE AS HIGH PRES MOVES TOWARD THE CAROLINAS DURING THE NEXT COUPLE OF DAYS. ALOFT...THE GULF IS DOMINATED BY WESTERLY UPPER WINDS. A JET STREAM BRANCH WITH CORE WINDS OF 70 KT CROSSES THE CENTRAL GULF AND SOUTH FLORIDA INTO THE W ATLC. A BAND OF TRANSVERSE HIGH CLOUDS IS ASSOCIATED WITH THIS JET. COLD AIR STRATOCUMULUS CLOUDS CONTINUES TO AFFECT THE SE QUADRANT OF THE GULF...AND ARE MOVING TOWARD THE YUCATAN PENINSULA UNDER A NELY WIND FLOW. THE FAR N GULF REMAINS CLEAR THIS EVENING. CARIBBEAN SEA... DUE TO THE COLD AIR ADVECTION ACROSS THE FLORIDA PENINSULA AND THE STRAITS OF FLORIDA...SEVERAL NEW LOW TEMPERATURE RECORDS WERE SET IN WEST-CENTRAL CUBA EARLY THIS MORNING. THE TOWN OF GUINES REPORTED THE LOWEST TEMPERATURE WITH 9.0 DEGREES CELSIUS OR 48.0 FAHRENHEIT FOLLOWED BY TAPASTE WHERE THE MERCURY DROPPED TO 9.2 DEGREES. THE COLD FRONT THAT BROUGHT THOSE COLD TEMPERATURES EXTENDS ACROSS THE WINDWARD PASSAGE AND JAMAICA TO NEAR CABO GRACIAS A DIOS NICARAGUA. THE FRONT IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS. UPPER DIFFLUENCE IS ALSO ENHANCING CONVECTION OVER THE SW CARIBBEAN AND SOUTHERN CENTRAL AMERICA. LOW LEVEL CLOUDS WITH EMBEDDED LIGHT RAIN IS NOTED NEAR THE FRONTAL BOUNDARY OVER HONDURAS. BROKEN COLD AIR STRATOCUMULUS CLOUDS ARE OBSERVED BEHIND THE FRONT COVERING THE NW CARIBBEAN. NELY WINDS ARE ALSO ADVECTING COLD AIR STRATOCUMULUS CLOUDS FROM THE W ATLC ACROSS THE BAHAMAS INTO CUBA. THE UPPER LEVELS OF THE CARIBBEAN ARE DOMINATED BY AN UPPER-LEVEL RIDGE ANCHORED ON A HIGH OVER CENTRAL AMERICA. THE TAIL END OF AN UPPER-LEVEL TROUGH LOCATED OVER THE TROPICAL N ATLC ENTERS THE SE CARIBBEAN THROUGH THE WINDWARD ISLANDS. ATLANTIC OCEAN... A DEEP LAYERED TROUGH EXTENDS FROM THE NE CONUS TO THE NORTHERN BAHAMAS WITH A JETSTREAM OF WINDS 90 TO 110 KT N OF 28N W OF 65W. AS OF 2100 UTC...THE ATTENDANT COLD FRONT ENTERS THE FORECAST AREA NEAR 31N60W THEN CONTINUES SW ACROSS THE WINDWARD PASSAGE AND THE CARIBBEAN SEA. A BAND OF MAINLY LOW CLOUDS WITH EMBEDDED SHOWERS IS ASSOCIATED WITH THE FRONT OVER THE ATLC. FURTHER EAST...A NARROW UPPER-LEVEL TROUGH EXTENDS INTO THE CENTRAL ATLC WITH A SURFACE TROUGH EXTENDING FROM 31N52W TO 23N57W. A CUT OFF UPPER LOW IS IN THE W TROPICAL ATLC NEAR 15N55W JUST TO THE W OF THE TROPICAL WAVE ALONG 52W/53W. AN UPPER TROUGH IS OVER THE E ATLC JUST SOUTH OF THE CANARY ISLANDS. THE ASSOCIATED COLD FRONT IS CURRENTLY DISSIPATING AND EXTENDS FROM A 1007 MB LOW INLAND OVER NW AFRICA ALONG 22N20W 23N30W 30N39W. A STRONG UPPER RIDGE COVERS THE REMAINDER OF THE TROPICAL ATLC ANCHORED INLAND OVER WEST AFRICA. THIS RIDGE IS HELPING TO INDUCE CONVECTION EMBEDDED WITHIN THE ITCZ AS WELL AS THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES AND THE BROAD AREA OF LOW PRES LOCATED NEAR 11N41W. $$ GR